Types of Phototherapy
Phototherapy is a widely used treatment for psoriasis, involving the use of ultraviolet (UV) light to slow skin cell growth, reduce inflammation, and minimize symptoms like itching and scaling.
Overview
Phototherapy is a widely used treatment for psoriasis, involving the use of ultraviolet (UV) light to slow skin cell growth, reduce inflammation, and minimize symptoms like itching and scaling. It is typically recommended when topical treatments do not provide sufficient relief or in more severe cases. Phototherapy is available in various forms, each with unique benefits. Below are the main types of phototherapy used in the treatment of psoriasis.
1. Narrowband UVB Therapy
Narrowband UVB (NB-UVB) is the most common type of phototherapy for psoriasis. It uses a specific wavelength of ultraviolet B (UVB) light (311-313 nm) that is highly effective in clearing psoriasis plaques. It can be administered in a healthcare setting or with home-use devices for eligible patients.
Mechanism: Narrowband UVB slows the excessive skin cell production and reduces inflammation.
Advantages: Fewer sessions required compared to broadband UVB; suitable for widespread and localized psoriasis.
Disadvantages: Potential for burning and increased skin cancer risk with prolonged use.
2. Broadband UVB Therapy
Broadband UVB (BB-UVB) was one of the earliest forms of phototherapy for psoriasis. It uses a broader range of UVB light (290-320 nm), which is less specific but still effective in managing psoriasis. This method is gradually being replaced by narrowband UVB due to its superior efficacy.
Mechanism: Similar to NB-UVB, broadband UVB reduces rapid skin cell turnover.
Advantages: Can be effective for mild to moderate psoriasis; more widely available.
Disadvantages: Increased risk of skin burning and side effects compared to NB-UVB.
3. Psoralen + UVA (PUVA) Therapy
PUVA combines a photosensitizing drug called psoralen with exposure to UVA light. The psoralen makes the skin more sensitive to UVA light, allowing deeper penetration to treat thicker plaques of psoriasis.
Mechanism: Psoralen is ingested or applied topically, and UVA light then penetrates the skin to slow down the excessive skin cell turnover.
Advantages: Particularly effective for treating thicker plaques and more stubborn cases of psoriasis.
Disadvantages: Higher risk of side effects, including nausea, skin burns, and increased long-term risk of skin cancer.
4. Excimer Laser
Excimer laser therapy delivers targeted UVB light (308 nm) to localized areas of psoriasis plaques. This precision treatment is ideal for small, stubborn patches of psoriasis that are resistant to other therapies.
Mechanism: Excimer laser emits a concentrated UVB light that directly targets affected skin areas, avoiding healthy skin.
Advantages: Effective for localized psoriasis, minimizes exposure to unaffected skin.
Disadvantages: Less suitable for widespread psoriasis, potential for skin irritation and blistering.
5. Combination Therapy
Sometimes, phototherapy is combined with topical or systemic treatments to improve results. For example, combining UVB with topical tar or systemic retinoids (ReUVB) can enhance the skin’s response to treatment, reducing the number of sessions required.
Mechanism: Combination therapies utilize phototherapy alongside medications that further suppress skin cell turnover.
Advantages: Enhanced effectiveness and faster clearance of psoriasis symptoms.
Disadvantages: May increase the risk of side effects depending on the additional treatment.
Is Phototherapy Right for You?
Phototherapy can offer significant relief for many patients, but it is not suitable for everyone. Factors such as the extent of your psoriasis, skin type, and overall health will influence whether phototherapy is a recommended treatment option. Always consult with a dermatologist to determine the best course of action for your individual needs.